Solve the Problem $x$ Years Can Be Described By $\mathrm { A } ( \mathrm { x } ) = 100 \mathrm { e } ^ { - 0.01569 \mathrm { x } }$

Multiple Choice

Solve the problem.
-Suppose the amount of a radioactive element remaining in a sample of 100 milligrams after $x$ years can be described by $\mathrm { A } ( \mathrm { x } ) = 100 \mathrm { e } ^ { - 0.01569 \mathrm { x } }$ . How much is remaining after 58 years? Round the answer to the nearest hundredth of a milligram.

A) $0.40 \mathrm { mg }$
B) $248.44 \mathrm { mg }$
C) $91.00 \mathrm { mg }$
D) $40.25 \mathrm { mg }$